There are about 7,000 rare genetic diseases (RDs) that affect more than one million Canadians. RDs have a devastating impact on Canadians: two-thirds cause significant disability, three-quarters affect children, more than half lead to early death, and almost all have no treatment. The cause of more than one-third of the 7000 RDs is currently unknown. To understand the remaining unsolved RDs, C4R-SOLVE is exploring new sequencing technologies and improving data sharing world-wide, enabling the discovery of new causes of RDs. By achieving its goal, the C4R-SOLVE project will more than double our ability to diagnose this one third of RD patients, while building the infrastructure and tools needed to improve RD diagnosis around the world.